These are the proceedings of a meeting celebrating Michael Thompson's seminal work on solar and stellar physics, as well as his major contributions to the development of the National Center for Atmospheric Research. The meeting also marked Michael J. Thompson's untimely death in October 2018. Michael played a key role in the development of helioseismology and its application to the study of the structure and dynamics of the solar interior, and he provided a strong foundation for the extension of seismic studies for other stars. After focusing for several years on more administrative activities, he was returning to leading the seismic studies of solar interior rotation and he was deeply involved in the understanding of the dynamics of the core of stars, when his life was tragically lost. The conference focused on dynamical aspects of the sun and stars, based on the large amount of data available on solar and stellar oscillations, and the extensive and detailed modelling now becoming feasible. Combining observations, seismic analysis, and modelling the meeting and this book serve as a fitting memorial to a close colleague and friend, much missed.

We stand at the threshold of an exciting era of Asteroseismology. In a few months' time, the Canadian small-satellite asteroseismology mission MOST will be laun ched. Danish and French missions MONS and COROT should follow, with the ESA mission Eddington following in 2007/8. Helioseismology has proved spec tacularly successful in imaging the internal structure and dynamics of the Sun and probing the physics of the solar interior. Ground-based observations have detected solar-like oscillations on alpha Centauri A and other Sun-like stars, and diagnostics similar to those used in helioseismology are now being used to test and constrain the physics and evolutionary state of these stars. Multi-mode oscillations are being observed in an abundance of other stars, including slowly pulsating B stars (SPB stars), delta Scuti stars, Ap stars and the pulsating white dwarfs. New classes of pulsators continue to be discovered across the Hertzsprung-Russell diagram. For good reason it was decided to entitle our conference 'Asteroseismology Across the HR Diagram' . Yet the challenges still to be faced to make asteroseismology across the HR diagram a reality are formidable. Observation, data analysis and theory all pose hard problems to be overcome. In conceiving this meeting, the aim of the organisers was to facilitate a cross-fertilization of ideas and approaches between researchers working on different pulsators and with different areas of expertise. We venture to suggest that in this the conference was a great success."

This book presents the proceedings of the IVth Azores International Advanced School in Space Sciences entitled "Asteroseismology and Exoplanets: Listening to the Stars and Searching for New Worlds". The school addressed the topics at the forefront of scientific research being conducted in the fields of asteroseismology and exoplanetary science, two fields of modern astrophysics that share many synergies and resources. These proceedings comprise the contributions from 18 invited lecturers, including both monographic presentations and a number of hands-on tutorials.

These are the proceedings of a meeting celebrating Michael Thompson's seminal work on solar and stellar physics, as well as his major contributions to the development of the National Center for Atmospheric Research. The meeting also marked Michael J. Thompson's untimely death in October 2018. Michael played a key role in the development of helioseismology and its application to the study of the structure and dynamics of the solar interior, and he provided a strong foundation for the extension of seismic studies for other stars. After focusing for several years on more administrative activities, he was returning to leading the seismic studies of solar interior rotation and he was deeply involved in the understanding of the dynamics of the core of stars, when his life was tragically lost. The conference focused on dynamical aspects of the sun and stars, based on the large amount of data available on solar and stellar oscillations, and the extensive and detailed modelling now becoming feasible. Combining observations, seismic analysis, and modelling the meeting and this book serve as a fitting memorial to a close colleague and friend, much missed.

We stand at the threshold of an exciting era of Asteroseismology. In a few months' time, the Canadian small-satellite asteroseismology mission MOST will be laun ched. Danish and French missions MONS and COROT should follow, with the ESA mission Eddington following in 2007/8. Helioseismology has proved spec tacularly successful in imaging the internal structure and dynamics of the Sun and probing the physics of the solar interior. Ground-based observations have detected solar-like oscillations on alpha Centauri A and other Sun-like stars, and diagnostics similar to those used in helioseismology are now being used to test and constrain the physics and evolutionary state of these stars. Multi-mode oscillations are being observed in an abundance of other stars, including slowly pulsating B stars (SPB stars), delta Scuti stars, Ap stars and the pulsating white dwarfs. New classes of pulsators continue to be discovered across the Hertzsprung-Russell diagram. For good reason it was decided to entitle our conference 'Asteroseismology Across the HR Diagram' . Yet the challenges still to be faced to make asteroseismology across the HR diagram a reality are formidable. Observation, data analysis and theory all pose hard problems to be overcome. In conceiving this meeting, the aim of the organisers was to facilitate a cross-fertilization of ideas and approaches between researchers working on different pulsators and with different areas of expertise. We venture to suggest that in this the conference was a great success."